640640160000 has 1215 divisors, whose sum is σ = 2498955788329. Its totient is φ = 157774848000.

The previous prime is 640640159989. The next prime is 640640160007. The reversal of 640640160000 is 61046046.

The square root of 640640160000 is 800400.

It is a perfect power (a square), and thus also a powerful number.

640640160000 is a `hidden beast` number, since 6 + 4 + 0 + 640 + 16 + 0 + 0 + 0 + 0 = 666.

It can be written as a sum of positive squares in 7 ways, for example, as 479151915264 + 161488244736 = 692208^2 + 401856^2 .

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (640640160007) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written in 134 ways as a sum of consecutive naturals, for example, 22091039986 + ... + 22091040014.

Almost surely, 2^640640160000 is an apocalyptic number.

640640160000 is a gapful number since it is divisible by the number (60) formed by its first and last digit.

640640160000 is the 800400-th square number.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 640640160000

640640160000 is an abundant number, since it is smaller than the sum of its proper divisors (1858315628329).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

640640160000 is an equidigital number, since it uses as much as digits as its factorization.

640640160000 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 146 (or 62 counting only the distinct ones).

The product of its (nonzero) digits is 3456, while the sum is 27.

The spelling of 640640160000 in words is "six hundred forty billion, six hundred forty million, one hundred sixty thousand".